Publications by authors named "Zafiris Daskalakis"

Objective: To qualitatively and quantitatively synthesize the literature on the efficacy and safety of magnetic seizure therapy (MST) in psychiatric disorders.

Methods: A literature search was conducted of the OVID Medline, OVID EMBASE, PsychINFO, CINAHL, Web of Science and Cochrane databases from inception to 14 January 2024, using subject headings and key words for "magnetic seizure therapy." Randomized controlled trials (RCTs), post-hoc analyses of RCTs, open-label trials, or case series investigating MST in adults with a verified psychiatric diagnosis and reporting on two possible primary outcomes (1) psychiatric symptom reduction (as measured by validated rating scale) or (2) neurocognitive outcomes (as measured by standardized testing), were included.

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Objective: This study aimed to optimally evaluate the effect of the long-interval intracortical inhibition (LICI) in the dorsolateral prefrontal cortex (DLPFC) through transcranial magnetic stimulation combined with electroencephalography (TMS-EEG) by eliminating the volume conductance with signal source estimation and using a realistic sham coil as a control.

Methods: We compared the LICI effects from the DLPFC between the active and sham stimulation conditions in 27 healthy participants. Evoked responses between the two conditions were evaluated at the sensor and source levels.

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Article Synopsis
  • Older adults with major depressive disorder (MDD) or mild cognitive impairment (MCI) are at increased risk for cognitive decline, making effective interventions crucial.
  • This study aimed to evaluate the effectiveness of combining cognitive remediation (CR) and transcranial direct current stimulation (tDCS) on cognitive decline in older adults with remitted MDD (rMDD) and/or MCI.
  • Results indicated that this intervention slowed cognitive decline over time but did not lead to immediate improvements in cognition after 2 months.
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Background: Intermittent theta burst stimulation (iTBS) is a form of repetitive transcranial magnetic stimulation (rTMS) that can be administered in a fraction of the time of standard rTMS. Applying multiple daily iTBS sessions (ie, accelerated iTBS) may enable patients to achieve remission more rapidly. However, questions remain regarding the optimal time interval between treatment sessions.

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In response to restrictions on electroconvulsive therapy (ECT) access during COVID-19, we designed a trial to assess the clinical outcomes service impacts, employing an extended course of accelerated intermittent theta burst stimulation (aiTBS), in patients with moderate to severe depression in need of ECT. This open label clinical trial was comprised of 3 phases: (i) an acute phase, where iTBS treatments were administered 8 times daily, for up to 10 days; (ii) a tapering phase of 2 treatment days per week for 2 weeks, followed by 1 treatment day per week for 2 weeks; and (iii) a symptom-based relapse prevention phase, whereby treatments were scheduled based on symptom re-emergence, for up to 6 months. Of the 155 patients who completed the acute phase of the study, the remission rate was 16.

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Article Synopsis
  • There is growing awareness that differences in brain function among individuals can significantly impact the effectiveness of repetitive transcranial magnetic stimulation (rTMS) treatments for schizophrenia.
  • A study analyzed data from a clinical trial where participants received either active or sham rTMS targeting the dorsolateral prefrontal cortex while performing a working memory task.
  • The findings indicated that active rTMS increased brain activity in the left DLPFC and reduced individual variability in activation patterns, which was connected to better attention performance.
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Article Synopsis
  • This study examined the neural connections associated with depressive and negative symptoms in schizophrenia spectrum disorders using data from neuroimaging and a trial of repetitive transcranial magnetic stimulation (rTMS).
  • By analyzing the data, three distinct functional brain circuitry patterns were identified that correspond to different symptom profiles: a general depressive factor, a factor for negative symptoms, and a guilt-related depression factor.
  • The findings highlight the complexity of these symptoms and suggest that rTMS can effectively reduce general depressive symptoms, but not those specifically related to guilt or negative symptoms.
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Decades of neuroimaging studies have shown modest differences in brain structure and connectivity in depression, hindering mechanistic insights or the identification of risk factors for disease onset. Furthermore, whereas depression is episodic, few longitudinal neuroimaging studies exist, limiting understanding of mechanisms that drive mood-state transitions. The emerging field of precision functional mapping has used densely sampled longitudinal neuroimaging data to show behaviourally meaningful differences in brain network topography and connectivity between and in healthy individuals, but this approach has not been applied in depression.

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Understanding how spontaneous brain activity influences the response to neurostimulation is crucial for the development of neurotherapeutics and brain-computer interfaces. Localized brain activity is suggested to influence the response to neurostimulation, but whether fast-fluctuating (i.e.

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Background: Late-life depression (LLD) is associated with cognitive impairment, but substantial heterogeneity exists among patients. Data on the extent of cognitive impairments are inconclusive, particularly in patients with treatment-resistant depression (TRD). We investigated the cognitive profiles of patients with treatment-resistant versus nonresistant LLD and aimed to identify distinct cognitive subgroups.

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Background And Objective: Repetitive transcranial magnetic stimulation (rTMS) is a safe and effective treatment for major depressive disorder (MDD); however, this treatment currently lacks reliable biomarkers of treatment response. TMS-evoked potentials (TEPs), measured using TMS-electroencephalography (TMS-EEG), have been suggested as potential biomarker candidates, with the N100 peak being one of the most promising. This study investigated the association between baseline N100 amplitude and 1 Hz right dorsolateral prefrontal cortex (R-DLPFC) accelerated rTMS (arTMS) treatment in MDD.

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Large-scale networks underpin brain functions. How such networks respond to focal stimulation can help decipher complex brain processes and optimize brain stimulation treatments. To map such stimulation-response patterns across the brain non-invasively, we recorded concurrent EEG responses from single-pulse transcranial magnetic stimulation (i.

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Identifying predictors of treatment response to repetitive transcranial magnetic stimulation (rTMS) remain elusive in treatment-resistant depression (TRD). Leveraging electronic medical records (EMR), this retrospective cohort study applied supervised machine learning (ML) to sociodemographic, clinical, and treatment-related data to predict depressive symptom response (>50% reduction on PHQ-9) and remission (PHQ-9 < 5) following rTMS in 232 patients with TRD (mean age: 54.5, 63.

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Background: As an established treatment for major depressive disorder (MDD), cognitive behavioral therapy (CBT) is now implemented and assessed in internet-based formats that, when combined with smartphone apps, enable secure text messaging. As an adjunct to such internet-based CBT (ICBT) approaches, text messaging has been associated with increased adherence and therapeutic alliance.

Objective: This study analyzed data from the intervention arm of a randomized control trial evaluating 24-week ICBT for MDD (intervention arm) against standard-care psychiatry (waitlist control).

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Background: Applying deep brain stimulation (DBS) to several brain regions has been investigated in attempts to treat highly treatment-resistant depression, with variable results. Our initial pilot data suggested that the bed nucleus of the stria terminalis (BNST) could be a promising therapeutic target.

Objective: The aim of this study was to gather blinded data exploring the efficacy of applying DBS to the BNST in patients with highly refractory depression.

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Background: Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for major depressive disorder (MDD), but substantial heterogeneity in outcomes remains. We examined a potential mechanism of action of rTMS to normalize individual variability in resting-state functional connectivity (rs-fc) before and after a course of treatment.

Methods: Variability in rs-fc was examined in healthy controls (baseline) and individuals with MDD (baseline and after 4-6 weeks of rTMS).

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In recent years, there has been debate about the effectiveness of treatments from different fields, such as neurostimulation, neurofeedback, brain training, and pharmacotherapy. This debate has been fuelled by contradictory and nuanced experimental findings. Notably, the effectiveness of a given treatment is commonly evaluated by comparing the effect of the active treatment versus the placebo on human health and/or behaviour.

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Whether individuals with mild cognitive impairment (MCI) and a history of major depressive disorder (MDD) are at a higher risk for cognitive decline than those with MCI alone is still not clear. Previous work suggests that a reduction in prefrontal cortical theta phase-gamma amplitude coupling (TGC) is an early marker of cognitive impairment. This study aimed to determine whether using a TGC cutoff is better at separating individuals with MCI or MCI with remitted MDD (MCI+rMDD) on cognitive performance than their clinical diagnosis.

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Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment in patients with depression, yet treatment response remains variable. While previous work has identified predictors of remission in younger adults, relatively little data exists in late-life depression (LLD). To address this gap, data from 164 participants with LLD from a randomized non-inferiority treatment trial comparing standard bilateral rTMS to bilateral theta burst stimulation (TBS) (ClinicalTrials.

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Background: Recent studies have reported significant advances in modeling the biological basis of heterogeneity in major depressive disorder, but investigators have also identified important technical challenges, including scanner-related artifacts, a propensity for multivariate models to overfit, and a need for larger samples with more extensive clinical phenotyping. The goals of the current study were to evaluate dimensional and categorical solutions to parsing heterogeneity in depression that are stable and generalizable in a large, single-site sample.

Methods: We used regularized canonical correlation analysis to identify data-driven brain-behavior dimensions that explain individual differences in depression symptom domains in a large, single-site dataset comprising clinical assessments and resting-state functional magnetic resonance imaging data for 328 patients with major depressive disorder and 461 healthy control participants.

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Over the past two decades noninvasive brain stimulation (NIBS) techniques have emerged as powerful therapeutic options for a range of psychiatric and neurological disorders. NIBS are hypothesized to rebalance pathological brain networks thus reducing symptoms and improving functioning. This development has been fueled by controlled studies with increasing size and rigor aiming to characterize how treatments induce clinically effective change.

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Background: Current evidence supports physical activity (PA) as an adjunctive treatment for major depressive disorder (MDD). Few studies, however, have examined the relationship between objectively measured PA and MDD treatment outcomes using prospective data.

Objective: This study is a secondary analysis of data from a 24-week internet-based, mindfulness-based cognitive behavioral therapy program for MDD.

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Major depressive disorder (MDD) is a leading cause of disability worldwide. One of the most efficacious treatments for treatment-resistant MDD is electroconvulsive therapy (ECT). Recently, magnetic seizure therapy (MST) was developed as an alternative to ECT due to its more favorable side effect profile.

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